Nikolai Bozhenov 650bf3e599 [BypassSlowDivision] Do not bypass division of hash-like values
Disable bypassing if one of the operands looks like a hash value. Slow
division often occurs in hashtable implementations and fast division is
never taken there because a hash value is extremely unlikely to have
enough upper bits set to zero.

A value is considered to be hash-like if it is produced by

1) XOR operation
2) Multiplication by a constant wider than the shorter type
3) PHI node with all incoming values being hash-like

Differential Revision: https://reviews.llvm.org/D28200


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@299329 91177308-0d34-0410-b5e6-96231b3b80d8
2017-04-02 13:14:30 +00:00
..
2017-03-06 21:10:40 +00:00
2017-03-13 20:00:25 +00:00